Seal Populations Flourishing Thanks to Protective Law

Updated at 7:21 am, April 28th, 2013

iStockphoto(WASHINGTON) — At a time when it seems like Congress can’t get anything right, environmentalists across the country are praising a 41-year-old federal law that is achieving exactly what its framers wanted.

The Marine Mammal Protection Act of 1972 prohibited killing, harassing, or even annoying all mammals that make the oceans along our shores their homes.

By the time the law was passed gray seals had all but disappeared from the beaches of New England. Fly over Cape Cod these days and you will likely see thousands of these seals, which once had been feared to be heading for extinction.

“You wouldn’t have seen gray seals at all in New England 50 years ago,” University of Vermont conservation biologist Joe Roman said. “They would have been shot, but now that they are protected these guys are out and about and very active.”

Roman is the lead author of a study published in the Annals of the New York Academy of Sciences documenting the rebounding of more than 200 individual stocks, or populations, of everything from seals to whales. They are doing well these days, Roman said in a telephone interview, because the federal law has worked.

“No other country has attempted such an audacious scientific undertaking,” the study notes.

But the law has worked too well, according to some. Marine mammals that come ashore for purposes such as procreation and raising their young have something in common with humans: We all want to live in the same place. Beaches are magnets for many mammals, not just seals and sea lions, and that has led to some inevitable confrontations.

“There are certainly some conflicts,” Roman conceded.

Fishermen and seals are natural enemies, vying for the same resources, and literally getting entangled in each other’s works. Legislation has been proposed in my state of Alaska to authorize the slaughter of sea otters that have moved north in great numbers to harvest the same crustaceans that humans consider delicious.

Two women are being sought by police in San Diego for allegedly kicking and beating seals that have taken over a popular beach in that city’s posh community of La Jolla. Tempers there have risen to the point that some residents want to see the seals driven off, but a judge ruled recently that the beach belongs to the seals.

Meanwhile, Cape Cod’s seals are attracting sharks to the region, according to researchers, so conflicts could turn bloody.

So it may seem like an uneasy truce between man and mammal, but Roman’s study shows that the rebounding of some endangered populations has been a great success, although it remains very much a work in progress.

The work is incomplete because most marine mammals are difficult and expensive to monitor. Humpback whales, for example, commute between Alaska and Hawaii, “so most of their lives are going to be beyond our view,” Roman said.

Another study concluded that even “precipitous declines would not be noticed for 72 percent of whale stocks,” because they are so hard, and expensive, to monitor.

“You can’t just sit on a coastline and monitor these species,” Roman said. It’s so difficult that it’s unknown whether 71 percent of the populations monitored under the law are getting better, or worse. Scientists think the answer is better, because the stocks that can be monitored are “trending” upward, but no one knows for sure.

Importantly, not a single stock that is being monitored has died out, according to the study. Some 19 percent are known to be improving, 5 percent are stable and 5 percent are decreasing.

The Marine Mammal Protection Act actually refocused wildlife officials on entire ecosystems. Because every species — like the much endangered right whale — is part of a larger ecosystem, many programs today are broader than a single species. International treaties to protect whales have been credited with curtailing the slaughter of these great animals, and they apply to all whales, with some exceptions.

There is something of an irony over the continuing conflict between humans and some marine mammals, Roman said. Some humans may hate them, because they are perceived to interfere with fishing, and there’s no doubt seals, sea lions and elephant seals can wreak havoc on a beautiful beach. But many people love them.

Whale watching alone brings in nearly $1 billion a year to coastal communities, according to the study.

“In New England, whale watching has arisen in places where fisheries have declined, so it’s another opportunity for employment,” Roman said. “People pay a fair amount of money to see whales, and even seals and porpoises and dolphins.”

Even the stuff they leave behind can be useful, according to Roman.

He and his colleagues have been studying whale pups and “the good news is,” he said, the pups dive deep to feed often, and “they are releasing nutrients at the surface in the form of feces. That enhances the growth of algae and seaweed,” which increases the organic productivity of the region.

So when the population of marine mammals rebounds, everybody gains, he argues.